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Influence of Storage Conditions on Metabolic Profile of Apples
Duroňová, Kateřina ; Vávrová, Milada (referee) ; Kráčmar, Stanislav (referee) ; Márová, Ivana (advisor)
The goal of presented dissertation has been complex analysis of changes in content of fatty acids, enzymatic and low-molecular antioxidants in apples and related evaluation of perception of originators of storage diseases for apples stored in various conditions. Main part of the work has been dedicated to study of the impact of storage of apples in modified atmosphere with reduced amount of oxygen and in reference “normal” atmosphere for six months. Next part of the work has been dedicated to study how apple storage in common, consumer affordable, conditions (storage in a cellar, in a refrigerator, and in room temperature) affects content of low-molecular antioxidants. For testing has been selected apple kinds Jonagored, Golden Delicious, Idared, Šampion, and Granny Smith. Within the scope of this work has been optimized the method for determination of fatty acids in plant material with higher content of wax. The measured values imply the apples are valuable source of many important nutrition substances like vitamins, provitamins and antioxidants. During the storage process these substances exhibit considerable protective function. Long-term storage, mainly in the atmosphere with reduced amount of oxygen (FAN), enables preservation of majority of these important nutrition substances depending on the kind of apple and conditions of storage. Freezing process is conservative to apples (mainly in the presence of protective substances), while in the process of drying the values of all monitored antioxidants decrease depending on temperature and conditions of drying. Upon the choice of the storage method one must consider nutrition, sensoric characteristic and consumer demands.
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Microbial contamination packaging glass
Bělohoubková, Tereza ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
The bachelor thesis contemplates the formation of microbial contamination during production of glass packaging used in food industry. The theoretical part defines the word packaging, its function and legislation of glass packaging. Glass packaging production is described as well as arising risks of potential microbial contamination. Unacceptable microorganisms with ability to live on the surface of glass packaging and possible determination of the microorganisms are characterized in the thesis. In the practical part swabs of produced glass packaging were analyzed by ATP bioluminescence and pH of the inner glass surface was determined to assess species of microorganisms able to live on glass surface. Conclusion of the thesis discusses establishments to lower the risk of microbial contamination.
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The negative effect of raw foods due to possible microbial contamination
Šťastná, Martina ; Hlaváček, Viliam (referee) ; Němcová, Andrea (advisor)
Raw diet is the current trend in nutrition, mainly because of the consumption of a balanced diet with a high proportion of health benefits. The basis is the consumption of fresh foods that have not undergone a heat treatment exceeding 42 - 45 ° C. The topic of the bachelor thesis is the general characterization of raw diet, safety of possible microbial contamination and determination of important nutrients and active substances contained in raw products. There are described the most widespread types of meals, approximation of raw diet in terms of its advantages and disadvantages. Also, there are described the most important bacteria, yeasts and molds occurring on fruits and vegetables. By selected methods described in the theoretical part, some nutrients and active ingredients in raw stick samples were determined. The experimental part describes the procedures and principles for the determination of these substances, and last but not least, the real-time PCR methods, agarose gel electrophoresis and the method of sample inoculation for selective solid media that have brought closer the possibility of occurrence of undesirable microorganisms in raw bars and cake. Despite the large number of benefits of raw food consumption and products made from it, it is necessary to take care of its health also in terms of possible contamination by microorganisms. The risk is that the food is not free from unwanted microorganisms during preparation. This is the reason why the raw products are consumed in the shortest possible time after opening, because they become easily a nutrition source for different types of microorganisms due to their composition.
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Posouzení vlivu země původu a způsobu zpracování na mikrobiotu vybraného koření
Menoušková, Karolína
The diploma thesis deals with the requirements for the quality of spices. It mainly deals with the microbial contamination of spices, factors of influence and possible means to prevent its contamination. Furthermore, the work deals with the characteristics of spices of the genus Capsicum, its range and possible use. In the practical part of the work, the microbial contamination of spices in peppers and chilli was determined. Individual spice samples differed depending on the country of origin, the method of technological processing, physical treatment and the content of capsaicin. During the microbiological analysis, the total number of microorganisms (CPM), the numbers of coliform bacteria and Escherichia coli, moulds and yeast, or the presence of Clostridum perfringens were monitored. The highest CPM value (4,49 log KTJ·g−1) was detected in the sample of ground chilli from China. A higher number of coliform bacteria and E. coli (2,49 log KTJ·g−1) was observed in the sample of sweet pepper from Spain. A significantly higher number of moulds and yeasts (3,13 log KTJ·g−1) was recorded in the sample of ground goulash pepper from the Czech Republic. In the case of Cl. perfringens, the presence of this bacterium was showed in 3 of 13 pepper and chilli spice samples. During the laboratory experiment, no significant deviations of occurrence of the monitored microorganisms were detected in comparison with the recommended limits or the results of scientific studies. The results show that microbial contamination may be affected by the country of origin, the physical treatment, or the alkaloid content of capsaicin, which evidences an antimicrobial activity. When monitoring the effect of technological processing on the spice microbiota, there was no statistically significant difference between the monitored pepper samples (P < 0,05).
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Mikroorganismy kontaminující nápoje z čerstvého ovoce a zeleniny (smoothie)
Keresztesová, Nela
The diploma thesis is focused on microorganisms contaminating drinks from fresh fruits and vegetables intended for direct consumption. The theoretical part focuses on technologies for the production of fruit and vegetable juices and the most common methods of preservation. Another part of the work is focused on microbial contamination (bacteria, fungi, yeasts and mycotoxins). In the experimental part, this work deals with microbiological analysis, which determined the presence of contaminating microorganisms. The microbiological quality was compared for fresh unprocessed juices intended for direct consumption with juices treated with high pressure or gentle pasteurization. It was confirmed that higher numbers of microorganisms were found in fresh juices, but also that an increase in microorganisms was noticeable after the minimum shelf life had expired.
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Microbial contamination packaging glass
Bělohoubková, Tereza ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
The bachelor thesis contemplates the formation of microbial contamination during production of glass packaging used in food industry. The theoretical part defines the word packaging, its function and legislation of glass packaging. Glass packaging production is described as well as arising risks of potential microbial contamination. Unacceptable microorganisms with ability to live on the surface of glass packaging and possible determination of the microorganisms are characterized in the thesis. In the practical part swabs of produced glass packaging were analyzed by ATP bioluminescence and pH of the inner glass surface was determined to assess species of microorganisms able to live on glass surface. Conclusion of the thesis discusses establishments to lower the risk of microbial contamination.
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The negative effect of raw foods due to possible microbial contamination
Šťastná, Martina ; Hlaváček, Viliam (referee) ; Němcová, Andrea (advisor)
Raw diet is the current trend in nutrition, mainly because of the consumption of a balanced diet with a high proportion of health benefits. The basis is the consumption of fresh foods that have not undergone a heat treatment exceeding 42 - 45 ° C. The topic of the bachelor thesis is the general characterization of raw diet, safety of possible microbial contamination and determination of important nutrients and active substances contained in raw products. There are described the most widespread types of meals, approximation of raw diet in terms of its advantages and disadvantages. Also, there are described the most important bacteria, yeasts and molds occurring on fruits and vegetables. By selected methods described in the theoretical part, some nutrients and active ingredients in raw stick samples were determined. The experimental part describes the procedures and principles for the determination of these substances, and last but not least, the real-time PCR methods, agarose gel electrophoresis and the method of sample inoculation for selective solid media that have brought closer the possibility of occurrence of undesirable microorganisms in raw bars and cake. Despite the large number of benefits of raw food consumption and products made from it, it is necessary to take care of its health also in terms of possible contamination by microorganisms. The risk is that the food is not free from unwanted microorganisms during preparation. This is the reason why the raw products are consumed in the shortest possible time after opening, because they become easily a nutrition source for different types of microorganisms due to their composition.
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Influence of Storage Conditions on Metabolic Profile of Apples
Duroňová, Kateřina ; Vávrová, Milada (referee) ; Kráčmar, Stanislav (referee) ; Márová, Ivana (advisor)
The goal of presented dissertation has been complex analysis of changes in content of fatty acids, enzymatic and low-molecular antioxidants in apples and related evaluation of perception of originators of storage diseases for apples stored in various conditions. Main part of the work has been dedicated to study of the impact of storage of apples in modified atmosphere with reduced amount of oxygen and in reference “normal” atmosphere for six months. Next part of the work has been dedicated to study how apple storage in common, consumer affordable, conditions (storage in a cellar, in a refrigerator, and in room temperature) affects content of low-molecular antioxidants. For testing has been selected apple kinds Jonagored, Golden Delicious, Idared, Šampion, and Granny Smith. Within the scope of this work has been optimized the method for determination of fatty acids in plant material with higher content of wax. The measured values imply the apples are valuable source of many important nutrition substances like vitamins, provitamins and antioxidants. During the storage process these substances exhibit considerable protective function. Long-term storage, mainly in the atmosphere with reduced amount of oxygen (FAN), enables preservation of majority of these important nutrition substances depending on the kind of apple and conditions of storage. Freezing process is conservative to apples (mainly in the presence of protective substances), while in the process of drying the values of all monitored antioxidants decrease depending on temperature and conditions of drying. Upon the choice of the storage method one must consider nutrition, sensoric characteristic and consumer demands.
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Decontamination of the large-scale facility
BURDA, Radek
The theoretical part of the thesis is divided in the five main chapters. First chapter generally defines the term ?contamination?, which is closely related to the decontamination. Second chapter is focused on the microbial contamination, defines infectious agents, the mechanisms of its spread and points out microbes most likely to be misused as a biological weapon. Third chapter of the theoretical part addresses the decontamination itself. It defines the decontamination in general aiming for microbial decontamination, i.e. the biological agent surface and environment removal. Two basic groups of decontamination e.g. physical and chemical procedures are mentioned in this chapter. Fourth chapter presents valid standards describing various types of examinations for the desinfecting preparations efficacy evaluation. The last chapter of the theoretical part covers large-scale facilities, defines them and describes experimental facilities at the Department of large-scale testing in the National institute for nuclear, chemical and biological protection in Kamenna. The aim of the thesis is to create own methodology of the disinfactant efficiency testing with emphasis on the real condition simulation. The decontamination was carried out by means of following methods: aerosol generator method, decontamination by evaporation, manual sprayer and engine sprayer respectively. For the analysis we chose these disinfactants: Chirosan? Plus, Incidin OxyDes, Kohrsolin? FF, Korsolex? basic, Persteril? 36 and Sanosil? Super 25 Ag. The disinfectant efficiency was tested in 30, 60 and 120 m3 facilities. The tested B-agents were: Bacillus anthracis, Bacillus atrophaeus, Escherichia coli, Staphylococcus aureus and Streptococcus pneumoniae. For the decontamination efficiency verification we used a modified surface assay, a modified suspension assay and an agarose assay. The following issues were of concern: We found out that, based on the analysis of different techniques of decontamination, the large-scale facility decontamination is feasible. The most effective method of decontamination appears the manual and engine spraying with the latter more convenient for spaces over the 30 m3 in the matter of time. The decontamination by evaporation was inefficient for the large-scale facility decontamination. Experiments revealed that method based on aerosol distribution is convenient for large-scale facility decontamination. However, the nature of decontaminating preparation has to be considered. All disinfactants tested have shown good bactericidal activity. Nevertheless, only Korsolex? basic a Persteril? 36 have shown sufficient sporicidal activity with equal effect. The disadvantage of the preparation Persteril? 36 is its significant corrosive activity, on the other hand is inexpensive. The preparation Korsolex? basic contains anticorrosive compounds, but is more expensive than Persteril? 36. Our results demonstrated that the most convenient method for the decomtamination of facilities up to the 30 m3 is the manual aerosol sprayer. For facilities of larger volume the engine sprayer decontamination is more convenient. From the preparations tested, only Korsolex? basic a Persteril? 36 are, with respect to advantages and disadvantages, usable in the Department of large-scale testing in the National institute for nuclear, chemical and biological protection in Kamenna.
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